Adjustable boring head for continuous mining machine



Nov. 15, 1966 s.. M. CHRISTIAN ADJUSTABLE BORING HEAD FOR CONTINUOUS MINING MACHINE 2 Sheets-Sheet 1 Filed Dec.

INVENTOR.

STEPHEN M CHRIS TIA N hwy Nov. 15, 1966 s.. M. CHRISTIAN ADJUSTABLE BORING HEAD FOR CONTINUOUS MINING MACHINE Filed Dec. 26, 1963 2 Sheets-Sheet 2 INVENTOR. STEPHEN M. CHRIST/A N United States Patent() 3,285,666 ADJUSTABLE BORING HEAD FOR CONTINUOUS MINING MACHINE Stephen M. Christian, Harvey, Ill., assignor, by mesne assignments, to Westinghouse Air Brake Company,

Pittsburgh, Pa., a corporation of Pennsylvania Filed Dec. 26, 1963, Ser. No. 333,308 6 Claims. (Cl. 299-80) A further object of the invention is to provide a radially 7 adjustable boring head for continuous mining machines of the boring type in which the adjusting mean-s retractibly moves the telescopic boring arm for tramming and is mechanically locked in its selected cutting positions by the adjusting means for the boring arm.

A still further object of the invention is to provide an improved form of radially adjustable boring head having a telescopic boring arm in which the boring arm is extended and retractibly moved by hydraulic jack means and is adjusted when the hydraulic jack means is in its extended position and is held in adjustment by the adjusting means therefore, independently of the hydraulic jack means.

These and other objects of the invention will appear from time to time as the following specification proceeds and with reference to the accompanying drawings where- FIGURE 1 is a longitudinal sectional view taken through a boring head constructed in accordance with the principles of the present invention;

FIGURE 2 is a fragmentary longitudinal sectional view of the boring head shown in FIGURE 1, drawn to the same scale as FIGURE 1, but showing the telescopic boring arm in its retracted position;

FIGURE 3 is a sectional view taken substantially along line 33 of FIGURE 1;

FIGURE 4 is a sectional view taken substantially along line 4-4 of FIGURE 1; and

FIGURE 5 is an end view of the telescopic boring arm looking at the boring arm along line 5-5 of FIGURE 3.

In the embodiment of the invention illustrated in the drawings, I have shown in FIGURE 1 a telescopic boring head 10 including a hollow drive shaft 11 having a hollow 'boring arm 12 extending radially therefrom.

The drive shaft 11 is shown as being supported intermediate its ends in a hub structure 13 on oppositely facing radial thrust bearings 15. The hub structure 13 is a conventional hub structure extending from the cutter frame (not shown) of a continuous mining machine. The hollow shaft 11 is journalled at its rear end in a wall 16 of the cutter frame (not shown) on anti-friction bearings '17. A spur gear 18 is keyed or otherwise secured to said hollow shaft and driven from a suitable motor (not shown) through a conventional system of reduction gearing. The boring arm 12 is shown in FIGURE 1 as being formed integrally with the forward end portion of the hollow shaft 11 and as having a cylindrical hollow interior portion in direct communication with the hollow interior portion of the hollow shaft 11. As herein shown the shaft 11 has only one boring arm extending radially therefrom. It should be understood, however, that two or more boring arms may be provided if desired.

The boring head 10 also has an annular pilot cutter support 19 mounted at the forward end thereof adjacent the axis of rotation thereof and projecting forwardly therefrom. Cutter bits 20 are mounted on said pilot cutter ICC support 19 in a conventional manner and project forwardly from the forward end of said pilot cutter support for making an annular pilot cut in the mine face. The boring arm 12 also has a cutter support 21 mounted thereon and projecting forwardly therefrom and having cutter bits 2 projecting from the forward face thereof for cutting an annular kerf spaced radially outwardly of the pilot cutter 19.

The interior cylindrical wall of the boring arm 12 forms a support for a hollow telescopic arm 23 having a closed outer end portion having an arcuate cutter support 25 mounted thereon and projecting forwardly therefrom. The cutter support 25 carries the usual cutter bits 26 for cutting an annular kerf spaced radially outwardly of the annular kerf cut by the cutter bits 22 carried by the cutter support 21.

The telescopic arm 23 generally conforms to the hollow interior portion of the boring arm 12 and has opposite flattened faces 26 engaged by shoes 27 keyed in position within the boring arm 12 by keys 29. The keys 29 extend within diametrically opposed slots 30 extending through the wall of the boring arm 12 into keyways 31 formed in the shoes 27. The slots 30 are closed by closure plates 32 retained in position by machine screws 33 which also extend through the keys 29 and are threaded at their inner ends in the shoes 27. The shoes 27 thus provide rigidity for cutting and retain the telescopic boring arm 23 from turning movement with respect to the boring arm 12 and accommodate full retractible movement of said telescopic boring arm within the boring arm 12.

Referring now in particular to the adjusting means for the telescopic boring arm 23, the arm 23 is extensibly moved into a selected cutting position and retractibly moved into a tramming position by operation of a slide 35 slidably carried within the hollow interior portion of the hollow shaft 11 and retained from turning movement with respect to said hollow shaft by a link 36 herein shown as having threads 37 extending therealong. The inner end of the link 36 extends between the furcations of a bifurcated portion 39 of the slide 35 and is pivotally connected thereto as by a pivot pin 40 extending transversely of the axis of rotation of the hollow shaft 11 and boring arm 12.

The opposite end of the link 36 from the pivot pin 40 is threaded within a threaded sleeve or nut 41, shown in FIGURE 3 as having trunnion pins 43 extending laterally therefrom in opposite directions and parallel to the pivot .pin 40, The trunnion pins 43 are in turn pivotal ly mounted in a clevis portion 45 of a piston 46. The clevis portion 45 is generally cylindrical in form and forms an inward continuation of the piston 46 and is of a split construction having a removable wall portion 47 accommodating the mounting of the trunnion pins 43 in said clevis portion. The removable portion 47 is secured to said clevis portion as by machine screws 49. The removable portion 47 likewise has a gib 50 engageable within-a groove 51 retaining the parts 45 and 47 from relative movement with respect to each other. The piston portion 46 is sealed to the hollow interior portion of the telescopic arm 23 as by an O-ring seal 53 and abuts a shoulder 55 extending inwardly of the cylindrical wall of the telescopic arm 23. A shaft 57 extends from the piston portion 46 outwardly along the telescopic arm 23 and has a reduced outer end portion 59 having 'a washer 60 thereon abutting an outwardly facing shouldered portion 61 of the hollow interior portion of the telescopic arm 23, 'The washer is retained to the end of the shaft 57 and to the shouldered portion 61 as by a nut 62. The shaft 57, piston 46 and clevis 45 are rotated to move the nut 41 along the threaded portion 37 of the link 36, to adjust the cutting position of the cutter arm 25 by a suitable wrench (not shown) engaging an oblong end portion 63 of said shaft. A lock plate 65 fits over the oblong end portion of the shaft 63 and is secured to an outer recessed portion 66 of the cutter support as by a machine screw 67, to positively lock the shaft 57 and nut or sleeve 41 from rotation when the tele-. scopic arm 23 is in the proper adjusted position, to position the cutter support 25 and cutter bits 26 to cut at a selected cutting diameter. The oblong end portion of the shaft 57 is so arranged with respect to the trunnion pins 43 that the axis of said trunnion pins will always be in the plane of the axis of the pin 40 when the cutter support 25 is in its adjusted position.

The slide 35 has a flattened forward end portion 69 fitting in a recess 70 when said slide is in its outermost position of adjustment to prevent turning movement of said slide with respect to the shaft 11 and to positively rotate said slide with said shaft.

The telescopic arm '23 has a slot 71 extending therealong the rear side thereof to receive the nut or sleeve 41 as the slide 35 is retractibly moved along the hollow shaft 11 to retract the telescopic arm 23 and cutter support 25 and thereby retractibly move the telescopic arm 23 and cutter support 25 into a retracted tramming position. When in the retracted tramming position shown in FIG- URE 2, the nut or sleeve 41 and link 36 fit within a slot 73 formed at the juncture of the hollow interior wall of the shaft 11 with the hollow interior wall of the boring arm 12.

The slide 35 is slidably moved along the hollow interior portion of the shaft 11 as by a double acting fluid pressure cylinder 75 having a piston rod 76 extensible therefrom. The cylinder 75 is shown in FIGURE 1 as having a shaft 77 extending from the head end thereof beyond the inner end of the hollow shaft 11 and supported on and held from rotation by a collar 79 keyed or otherwise secured to a reduced end portion 80 of said shaft, and by a retainer 81 secured to the rear face of the wall 16, as by machine screws 82, and suitably supporting the collar 79 and holding said collar from rotation. A nut 83 threaded on the outer end of the reduced end portion 80 of the shaft 77 serves to retain said shaft to the collar 79 and retainer 81. The cylinder 75 is supported at its inner end within the hollow shaft 11 on an anti-friction bearing 85. The piston rod 76 is shown in FIGURE 1 as having a threaded free end portion threaded within a hub 87 of a retainer disk 88. The retainer disk 88 is mounted within a hollow portion 89 of the slide 35 and is retained to said slide by anti-friction thrust bearings 90, 90 engaging opposite faces of said disk. An annular end cap 91 is secured to the inner end of the slide 35 'and encircles the piston rod 76 and abuts the outer thrust bearing 90. The cylinder 75 and piston rod 76 may thus extensibly and retractibly move the slide 35 along the hollow interior portion of the shaft 11, to position the telescopic arm 23 and cutter support 25 in the cutting position shown in FIGURE 1,

and into the retracted tramming position shown in FIG- URE 2. I

' When the arm 23 and cutter support 25 are in the extended position shown in FIGURE 1, the end 69 of the slide 35 engages within the groove or slot 70 and is held from twisting movement by said groove or slot. When the slide 35 is in the position shown in FIGURE 1, the axis of the pivot pin 40 is over center with respect to the axis of the pivot pin 43, and is ahead of the axis of said pivot pin. The locking plate 65, however, locks the axes of the pins 43 and 40 in a common plane. The cutting forces are thus taken directly on the link 36 and slide 35, the

off center positions of the axes of said pivot pins, locking the telescopic arm 23 in its cutting position independently of the cylinder 75 and piston rod 76. The cylinder 75 and piston rod 76 thus perform no holding function and leakage from one side of the cylinder to the other back to tank will have no affect on the position of the telescopic arm 23.

While I have herein shown and described one form in which the invention may be embodied, it may readily be understood that various variations and modifications in the invention may be attained without departing from the spirit and scope of the novel concepts thereof.

I claim as my invention:

1. In a rotary boring head for continuous mining machines, a hollow shaft journalled for rotation about a horizontal axis, at least one hollow boring arm project ing radially of said shaft and having communication with the hollow interior portion of said shaft, a slide movable along said shaft by power, a telescopic arm telescopically mounted in said hollow boring arm and having a cutter support projecting forwardly therefrom, guide means for said telescopic arm retaining said telescopic arm from rotation, an adjustable linkage connection pivotally connected between said slide and said telescopic arm for extensibly and retractibly moving said telescopic arm upon movement of said slide along said hollow shaft, means operable from the outside of said telescopic arm for adjusting the length of said adjustable linkage connection and the cutting position of said telescopic arm and cutter support, and a recess at the forward end portion of said hollow shaft engaged by said slide and holding said slide from turning movement with respect to said shaft when said linkage connection is in its extended position, and accommodating the positioning of said linkage connection beyond a dead center position, to retain said telescopic arm and cutter support in position.

2. In an adjustable rotary boring head particularly adapted for continuous mining machines and the like, a hollow shaft, a hollow boring arm extending radially of said shaft, bearing means supporting said shaft for rotation about a horizontal axis, a telescopic boring anrn mounted in said hollow boring arm for telescopic movement therealong and having a cutter support projecting forwardly therefrom, means for adjustably moving said telescopic arm along said hollow boring arm and retaining said telescopic arm in position, comprising a slide movable along said shaft, a fluid pressure operated cylinder and piston mounted in said shaft and having operative connection with said slide for moving said slide along said hollow shaft, an adjustable link having a first part transversely pivoted to said slide and having a second part movable relative to said one part and transversely pivoted within said telescopic arm for movement about an axis parallel to the axis of connection of said first part to said slide, and means operable from the outside of said telescopic arm for moving said second part along said first part and adjusting the length of said linkage connection, upon full extensible movement of said slide beneath said telescopic arm, to vary the position of said telescopic arm with respect to said rotary boring arm.

3. In an adjustable rotary boring head particularly adapted for continuous mining machines and the like, a hollow shaft, a hollow boring arm extending radially of said shaft, bearing means supporting said shaft for rotation about a horizontal axis, a telescopic boring arm mounted in said hollow boring arm for telescopic movement therealong and having a cutter support projecting forwardlytherefrom, means for adjustably moving said telescopic arm along said hollow boring arm and retaining said telescopic arm in position, comprising a slide movable along said shaft, a fluid pressure operated cylinder and piston mounted in said shaft and having operative connection with said slide for moving said slide along said hollow shaft, an'adjustable link having va first part transversely pivoted to said slide and having a second part movable relative to said one part and transversely'pivoted within said telescopic arm for movement about an axis parallel to the axis of connection of said first part to said slide, and means operable from the outside of said telescopic arm for moving said second part along said first part and adjusting the length of said linkage connection, upon full extensible movement of said slide beneath said tele- .scopic arm, to vary the position of said telescopic arm with respect to said rotary boring arm, said slide having a reduced advanced end portion, and a recess at the forward end of said shaft receiving said slide and retaining said slide from turning movement with respect to said shaft and accommodating said cylinder and piston to position the axis of pivotal connection of said adjustable link to said slide forwardly of the axis of connection of said other part to said telescopic arm, to effect the locking of said telescopic arm in a cutting position independently of said cylinder and piston by the overcenter positioning of said pivotal axes with respect to each other.

4. An adjustable boring head particularly adapted for continuous mining machines and the like comprising, a hollow shaft journalled for rotation about a horizontal axis, a hollow boring arm projecting radially of said shaft and having communication wtih the hollow interior portion of said shaft, a telescopic arm telescopically mounted in said hollow boring arm, a slide movable along said shaft for extensibly and retractibly moving said telescopic arm with respect to said boring arm, power means for moving said slide along said shaft, and an adjustable linkage connection between said slide and telescopic arm comprising a threaded link and nut, one being transversely pivoted to said slide and the other being transversely pivoted to said telescopic arm, and a shaft turnable from the outside of said telescopic arm for turning said nut relative to said shaft when said slide is in extended relation along said hollow shaft and varying the position of said telescopic arm with respect to said boring arm.

5. An adjustable boring head of the class described comprising a hollow shaft journalled for rotation about a horizontal axis, a hollow boring arm projecting radially of said shaft and having communication with the hollow interior thereof, a telescopic arm telescopically mounted in said hollow boring arm, a slide movable along said shaft for extensibly and retractibly moving said telescopic arm with respect to said boring arm, a shaft turnably mounted in said telescopic arm for turning movement about the axis thereof and retained from axial movement with respect to said telescopic arm, and turnable from the outside of said arm, and an adjustable linkage connection between said slide and said shaft comprising a threaded link and nut, one being transversely pivoted to said slide and the other being transversely pivoted to said shaft and adjustably moved relative to each other by turning movement of said shaft from the outside of said telescopic arm, when said slide is in extended relation with respect to said telescopic arm, said shaft having an irregular outer end portion, and a locking member engageable with said irregular outer end portion of said shaft and locking the transverse pivotal axes of said nut and link in the same common plane when said telescopic arm is in an adjusted position.

6. An adjustable rotary boring head particularly adapted for continuous mining machines and the like, comprising a hollow shaft journalled for rotation about a horizontal axis, a hollow boring arm projecting radially of said shaft and having communication with the hollow interior portion of said shaft, a telescopic arm telescopically mounted in said hollow boring arm, a slide movable along said shaft for extensibly and retractibly moving said telescopic arm with respect to said boring arm, power means for moving said slide along said shaft, a threaded link transversely pivoted to said slide, a shaft rotatably mounted within said telescopic arm and turnable from the outside of said arm, a clevis extending from said shaft, and a nut threaded on said threaded link and trunnioned on said clevis for pivotal movement with respect thereto about an axis parallel to the axis of connection of said threaded link to said slide, said slide moving the axis of connection of said link to said slide forwardly of the axis of connection of said nut to said clevis to retain said boring arm in position independently of the power means for moving said slide along said hollow shaft, and said clevis being turnable from the outside of said boring arm for adjusting the length of said threaded linkage connection and the position of said telescopic arm with respect to said boring arm.

References Cited by the Examiner UNITED STATES PATENTS 2,801,094 7/1957 Ball 299 3,035,822 4/1962 Lundquist et al 299-61 ERNEST R. PURSER, Primary Examiner. 

4. AN ADJUSTABLE BORING HEAD PARTICULARLY ADAPTED FOR CONTINUOUS MINING MACHINES AND THE LIKE COMPRISING, A HOLLOW SHAFT JOURNALLED FOR ROTATION ABOUT A HORIZONTAL AXIS, A HOLLOW BORING ARM PROJECTING RADIALLY OF SAID SHAFT AND HAVING COMMUNICATION WITH THE HOLLOW INTERIOR PORTION OF SAID SHAFT, A TELESCOPIC ARM TELECOPICALLY MOUNTED IN SAID HOLLOW BORING ARM, A SLIDE MOVABLE ALONG SAID SHAFT FOR EXTENSIBLY AND RETRACTIBLY MOVING SAID TELESCOPIC ARM WITH RESPECT TO SAID BORING ARM, POWER MEANS FOR MOVING SAID SLIDE ALONG SAID SHAFT, AND AN ADJUSTABLE LINKAGE CONNECTION BETWEEN SAID SLIDE AND TELESCOPIC ARM COMPRISING A THREADED LINK AND NUT, ONE BEING TRANSVERSELY PIVOTED TO SAID SLIDE AND THE OTHER BEING TRANSVERSELY PIVOTED TO SAID TELESCOPIC ARM, AND A SHAFT TURNABLE FROM THE OUTSIDE OF SAID TELESCOPIC ARM FOR TURNING SAID NUT RELATIVE TO SAID SHAFT WHEN SAID SLIDE IS IN EXTENDED RELATION ALONG SAID HOLLOW SHAFT AND VARYING THE POSITION OF SAID TELESCOPIC ARM WITH RESPECT TO SAID BORING ARM. 